29 research outputs found
Cartographie électro-anatomique tridimensionnelle et ablation par radiofréquence comme nouveau traitement d'une arythmie provoquée par une voie accessoire chez un cheval
No full textThis case report describes the diagnosis and treatment of an atrioventricular accessory pathway (AP) in a horse by three-dimensional electro-anatomical mapping (3D EAM) and radiofrequency catheter ablation (RFCA). During routine check-up of the horse, intermittent ventricular pre-excitation was noticed on the electrocardiogram (ECG), characterized by a short PQ interval and abnormal QRS morphology. A right cranial location of the AP was suspected from the 12-lead ECG and vectorcardiography. After precise localization of the AP using 3D EAM, ablation was performed and AP conduction was eliminated. Immediately after recovery from anesthesia an occasional pre-excited complex was still observed, but a 24-hour ECG and an ECG during exercise 1 and 6 weeks after the procedure showed complete disappearance of pre-excitation. This case shows the feasibility of 3D EAM and RFCA to identify and treat an AP in horses
Equine 3D electro-anatomical mapping in sinus rhythm elucidates the electrocardiogram and cardiac electrical activation pattern
No full textUnderstanding the depolarisation pattern of the equine heart under normal physiological conditions, and its relationship to the surface electrocardiogram (ECG), is of uppermost importance before any further research can be done about the pathophysiology of complex arrhythmias. The purpose was to use a 3D electro-anatomical mapping system under general anaesthesia to evaluate the qualitative and quantitative atrial and ventricular depolarisation patterns and correlation with the surface ECG in 7 healthy horses in sinus rhythm. Bipolar activation maps of the endocardium were analysed. The first atrial activation was located at the height of the crista terminalis. Only one interatrial conduction pathway was recognised. The first and second P wave deflections represented the right and left atrial depolarisation, respectively. His bundle electrograms could be recorded in 5 out of 7 horses. Left ventricular activation (Fig. 1 to 3) started at the mid septum, right ventricular activation apically from the supraventricular crest. This was followed by separate depolarisations at the height of the mid free wall. Further ventricular depolarisation occurred in an explosive pattern. Electrically active tissue could be found in all pulmonary veins. In contrast to findings of previous studies, all parts of the ventricular depolarisation contributed to the surface ECG QRS complex. This study provides a reference for the normal sinus impulse endocardial propagation pattern and for conduction velocities in equine atria and ventricles. This information allows to improve ECG reading and develop better recording techniques, such as new 12-lead ECG configurations, in horses
Three‐dimensional electro‐anatomical mapping and radiofrequency ablation as a novel treatment for atrioventricular accessory pathway in a horse: A case report
No full textAbstract We describe the diagnosis and treatment of an atrioventricular accessory pathway (AP) in a horse using 3‐dimensional electro‐anatomical mapping (3D EAM) and radiofrequency catheter ablation (RFCA). During routine evaluation of the horse, intermittent ventricular pre‐excitation was identified on the ECG, characterized by a short PQ interval and abnormal QRS morphology. A right cranial location of the AP was suspected from the 12‐lead ECG and vectorcardiography. After precise localization of the AP using 3D EAM, ablation was performed and AP conduction was eliminated. Immediately after recovery from anesthesia an occasional pre‐excited complex still was observed, but a 24‐hour ECG and an ECG during exercise 1 and 6 weeks after the procedure showed complete disappearance of pre‐excitation. This case shows the feasibility of 3D EAM and RFCA to identify and treat an AP in horses
Three dimensional ultra‐high‐density electro‐anatomical cardiac mapping in horses : methodology
No full textBackground: Ultra-high-density cardiac mapping allows very accurate characterisation of atrial and ventricular electrophysiology and activation timing.
Objective: To describe the technique and evaluate the feasibility of magnetic electroanatomical mapping of the equine heart.
Study design: In vivo experimental method development.
Methods: A mapping system using an 8.5F bidirectional deflectable catheter with a deployable mini-basket (3–22 mm) containing 64 electrodes divided over eight splines was evaluated. Based upon predefined beat acceptance criteria, the system automatically acquires endocardial electrograms and catheter location information. Electro-anatomical maps were acquired from four horses in sinus rhythm under general anaesthesia.
Results: All endocardial areas within each chamber could be reached. Access to the left atrium required the use of a deflectable sheath. With the exception of the left atrial map of horse 1, all four chambers in all four horses could be mapped. Optimisation of the beat acceptance criteria led to a reduction in manual correction of the automatically accepted beats from 13.1% in the first horse to 0.4% of the beats in the last horse.
Main limitations: Only a limited number of horses were included in the study.
Conclusion: Ultra-high-density 3D electro-anatomical mapping is feasible in adult horses and is a promising tool for electrophysiological research and characterisation of complex arrhythmias
Detection of the origin of atrial tachycardia by 3D electro‐anatomical mapping and treatment by radiofrequency catheter ablation in horses
No full textBackground: Atrial tachycardia (AT) can be treated by medical or electrical cardiover-
sion but the recurrence rate is high. Three-dimensional electro-anatomical mapping,
recently described in horses, might be used to map AT to identify a focal source or
reentry mechanism and to guide treatment by radiofrequency ablation.
Objectives: To describe the feasibility of 3D electro-anatomical mapping and radi-
ofrequency catheter ablation to characterize and treat sustained AT in horses.
Animals: Nine horses with sustained AT.
Methods: Records from horses with sustained AT referred for radiofrequency abla-
tion at Ghent University were reviewed.
Results: The AT was drug resistant in 4 out of 9 horses. In 8 out of 9 horses, AT origi-
nated from a localized macro-reentrant circuit (n = 5) or a focal source (n = 3) located
at the transition between the right atrium and the caudal vena cava. In these 8 horses,
local radiofrequency catheter ablation resulted in the termination of AT. At follow-
up, 6 out of 8 horses remained free of recurrence.
Conclusions and Clinical Importance: Differentiation between focal and macro-
reentrant AT in horses is possible using 3D electro-anatomical mapping. In this study,
the source of right atrial AT in horses was safely treated by radiofrequency catheter
ablation
Successful caudal vena cava and pulmonary vein isolation in healthy horses using 3D electro‐anatomical mapping and a contact force‐guided ablation system
No full textBackground: Recently, treatment of equine atrial tachycardia by three-dimensional electro-anatomical mapping (3D EAM) and radiofrequency catheter ablation (RFCA) has been described. Myocardial sleeves in the caudal vena cava and pulmonary veins are a potential trigger for initiation and perpetuation of atrial tachycardia and atrial fibrillation in the horse. Isolation of these myocardial sleeves by RFCA may be an effective treatment for these arrhythmias.
Objectives: To describe the feasibility of 3D EAM and RFCA to isolate caudal vena cava and pulmonary veins in adult horses using 3D mapping and a contact force (CF)-guided ablation system.
Study design: In vivo experiments.
Methods: 3D EAM and RFCA was performed in five horses without cardiovascular disease under general anaesthesia, using the CF-guided system CARTO®3. Point-by-point RFCA aimed for isolation of caudal vena cava and pulmonary veins. Radiofrequency energy was delivered in power-controlled mode with a target power of 45 W, CF between 10 and 15 g and 30 mL/min irrigation rate, until an ablation-index of 450–500 was reached.
Results: In the right atrium, myocardial sleeves of the caudal vena cava were isolated (n = 5). In the left atrium, isolation of ostium II (n = 3), ostium III (n = 1) and ostium I, II and III en bloc (n = 1) was performed. Successful isolation was confirmed by entrance and exit block.
Main limitations: Horses were euthanised at the end of the procedure, so long term effects such as potential reconnection of isolated veins could not be studied.
Conclusions: This is the first description of 3D EAM and RFCA with CARTO®3 in horses, thereby showing the technical feasibility and successful caudal vena cava and pulmonary vein isolation. CF measurement allowed monitoring of catheter-tissue contact, resulting in efficient acute lesion creation as confirmed by entrance and exit block. This is a promising treatment for cardiac arrhythmias in horses
First successful caudal vena cava and pulmonary vein isolations in healthy horses using 3D electro-anatomical mapping and a new, contact force-guided ablation system (CARTO® 3)
No full textIntroduction:
Recently, treatment of atrial tachycardia by three-dimensional electro-anatomical
mapping (3D EAM) and radiofrequency catheter ablation (RFCA) was described.
Recurrence was still seen in some patients, probably related to poor catheter-tissue
contact. A new mapping system (CARTO®3) allows real-time assessment of cathetertissue
contact by measuring contact-force (CF). Adequate contact ensures effective
ablation lesions which improves procedural success and reduces recurrence.
Methods:
3D EAM and RFCA was performed under general anaesthesia in the right and left atrium
in 5 healthy horses in sinus rhythm, using CARTO®3. RFCA aimed for isolation of the
caudal vena cava (CaVC) and pulmonary veins, two regions that harbour the source of
arrhythmia in horses with atrial arrhythmias. In the right atrium, point-by-point ablation
was performed to isolate the myocardial sleeves of CaVC (n=5) (Fig. 1). In the left
atrium, isolation of ostium II (n=3), ostium III (n=1) and ostium I-II-III en bloc (n=1)
was performed. Radiofrequency (RF) energy was delivered in power-controlled mode with
a target power of 35-45W, CF between 10-15g and irrigation rate of 30ml/min, until an
ablation-index of 450-500 was reached.
Results:
All targeted locations could be isolated, which was confirmed by absence of conduction
and absence of capture while pacing distal from the ablation line. Isolation of the CaVC,
ostium II, ostium III and ostium I-II-III required 12-28, 9-34, 19 and 59 RF applications.
Conclusion:
This is the first description of 3D EAM and RFCA with CARTO®3 system in horses,
thereby showing the applicability of successful CaVC and pulmonary vein isolation in
horses. CF measurement allowed efficient monitoring of catheter-tissue contact resulting
in efficient lesion creation.
Clinical relevance:
3D EAM and RFCA using real-time CF measurement allows CaVC and pulmonary vein
isolation, a promising new treatment strategy for arrhythmias originating from the right
and the left atrium in adult horses
Feasibility and safety of high-resolution three-dimensional electroanatomical mapping of the complete heart in dogs
No full textBACKGROUND
Three-dimensional electroanatomical mapping (3D EAM) has expanded radiofrequency catheter ablation (RFCA) applications in humans to almost all complex arrhythmias and has drastically reduced fluoroscopy use, yet its potential in dogs is poorly investigated.
OBJECTIVES
To assess the feasibility and safety of 3D EAM of all four heart chambers in dogs using minimal fluoroscopy.
ANIMALS
Eight Beagles (median weight 12.2 kg (11.2–15.7)).
METHODS
Prospective experimental trial. Three-dimensional EAM was attempted during sinus rhythm under general anesthesia using a 22-electrode mapping catheter and CARTO 3 system. Left heart catheterization was achieved by retrograde transaortic access (n=4) or transseptal puncture (TSP) (n=4). Primary outcomes included feasibility, safety and fluoroscopy time.
RESULTS
Successful 3D EAM of the right atrium and ventricle was achieved in all dogs. Left atrial and ventricular 3D EAM was achieved in six and seven dogs respectively. Median fluoroscopy time was 6.8 min (0.0–45.1) and almost exclusively associated with TSP. Complications requiring intervention occurred in one dog only and were a transient third-degree atrioventricular block after interatrial septum engagement, which reversed after intracardiac pacing (10.3 min), and development of pericardial effusion following TSP treated by pericardiocentesis. Perioperative self-limiting arrhythmias were frequently observed. Only two dogs received lidocaine to resolve intra-operative ventricular tachycardia.
CONCLUSIONS AND CLINICAL IMPORTANCE
Three-dimensional EAM of all cardiac chambers is feasible, requires minimal fluoroscopic assistance and is promising to guide RFCA of arrhythmias in dogs. Complications were mainly related to TSP and similar to those reported in people
